Pneumatic loom



June 16, 1964 Filed March 11, 1963 L. TE STRAKE PNEUMATIC LOOM 4Sheets-Sheet 1 L. TE STRAKE PNEUMATIC LOOM June 16, 1964 4 Sheets-Sheet2 Filed March 11, 1963 L. TE STRAKE PNEUMATIC LOOM June 16, 1964 4Sheets-Sheet 3 Filed March 11, 1963 June 16, 1964 L. TE STRAKE 3,137,322PNEUMATIC LOOM Filed March 11, 1963 4 Sheets-Sheet 4 United StatesPatent 3,137,322 PNEUMATIC LOOM Lambertus te Strake, Deurne, NorthBrabant, Netherlands Filed Mar. 11, 1963, Ser. No. 264,143 Claimspriority, application Netherlands Feb. 24, 1960 10 Claims. (Cl. 139-127)This invention relates to a device for transporting threads by means ofair, and to a loom provided with such a device for blowing the weftthread into the shed. a

A natural selvedge can be made with pneumatic looms by blowing the weftthreads in the shape of hairpins into the shed, i.e., by blowing a firstmeasured thread-length into the shed from one side of the shed andstoring a second length, of the same length as the first, of the samethread provisorily outside the shed. When the first measured length ofthe weft thread has been introduced and the strike has beenaccomplished, the second measured length of the weft thread, which hasbeen stored provisorily outside the shed, is blown into the shed.Preferably, this occurs at both sides of the shed, so that at the twosides of the cloth a selvedge is formed which is not thicker than themiddle part of the cloth.

It is an object of this invention to provide improved loom apparatus. Itis a further object of this invention to provide weft insertingapparatus whereby the manufacture of the above described selvedge issimple.

According to the invention, the objects are achieved by the use of ablowing device of the injector type, in which primary air is injectedthrough a blowing nozzle onto a mixing tube defined by. a shaft, whichstores a loop of thread, and also defines conduit communicating with themixing tube for conveying secondary air to the mixing tube.

This arrangement has the advantage that the thread coming into contactwith the air jet from the blowing nozzle already is in a moving aircolumn. Further, the thread in the moving air column in the shaftdoes'not make a frictional contact with the shaft walls, so that itbecomes possible to blow the thread into the shed with a a substantiallysmaller quantity of air and yet with a larger velocity. V

A preferred embodiment is shown herein in which the blowing nozzle isspaced from the open end of the shaft so that a part of the shaft servesas a mixing tube for the secondary air.

With the-apparatus ofthis invention, a superatmospheric pressure of onlyone atmosphere sufiices for blowing a Weft thread over a certaindistance into the shed, in contrast to the previous well-known pneumaticlooms in which a superatmospheric pressure of atmospheres is used, andin contrast to a blowing nozzle provided with a mixing tube in which ahole or slit is formed for secondary air and in which a superatmosphericpressure of 3 atmospheres is required. s

The slit described in this construction is in the shape of a flat,longitudinally extending, narrow slit formed in the central part of theshaft. communicating at each side with channels, giving across-sectional appearance of a bar bell. Blowing devices or nozzles arepositioned in enlargements of each of the channels. This providestheadvantage that no separatefeeding device for the weft thread needs to beused with the weft threads for obtaining a natural selvage to be laid inthe shed in the form of v a hairpin. The hairpin configuration isobtained when halves of a measured length of a thread are blown successively into the shed by the two free ends. v

Other objects, advantages, and features of the invention will becomeapparent when the following descrip-.

V 3,137,322 Patented June 16,1964

device mounted on part of a loom;

FIG. 2 is similar to FIG. 1 showing that the thread which has been blowninto the .shed is beaten up before the next weft is inserted;

FIGS. 3 and 4 are plan views in section witha portion of the insertingnozzle cut away, the section in FIG. 3 being taken along line3 -3 ofFIG. 9 and the section in FIG. 4 being taken along line 4-4 of FIG. 9;

1 FIG. 5 is a cross-sectional view taken along line 55 of FIG. 6 showinga portion of the nozzle; 7

FIG. 6 is a fragmentary plan view partly broken away and sectioned nearthe open end of the nozzle;

FIG. 7 is a side view of the nozzle taken at the open end; I v

FIG. 8 is a fragmentary perspective view of a transparent model takenfrom the open end of the nozzle; and 2 perspective of driving mechanismline 12 and runs, via a thread guide 13, along a thread collectingsuction nozzle 14 in which a suction action prevails (suction can occurintermittently). A third'clamp -15, in front of the nozzle 14, isprovided for a purpose hereinafter described. The thread 12 then passesto the open end 16 of an inserting nozzle or shaft 17. The shaft 17 willbe described hereinafter in detail in connection with FIGS. 5-9.

Two. nozzles 18 and 19 are defined by the shaft 17 and in the positionof the shaft 17 as shown in FIG. 1 there is a loop of thread in theshaft 17, the length of which loop correspondsto the width of the shed.The wrap threads are indicated bythe numeral 20. In that part of thecycle shown in FIG. 1, the nozzle 18 comes into action and blows theloop out of the shaft 17 into the shed. Thereupon, theshaft17 turns, ashereinafter described,

to the position shown in FIG. 2 and the thread passes from the cloth 21to the thread clamp 15. When the nozzle 18 is activated, the clamp 15'is closed and retains the thread in order to besure that thecorrectlength 'of the thread is'blown into the shed. The clamp 15 iscontrolled mechanically, its operation being a function of the yield ofthe feeding roll 11. In the position shown in FIG. 2,. the clamp 15 is.open. Since the yield of the feeding roll 11 is constant, the correctquantity of yarn is stored provisorily in the nozzle 14. Then the shaft17 exerts a suction actionon the thread so that anew loop of the threadis drawn into the shaft as shown in FIG. 2. Since at a given moment theshaft 17 does not continue to blow the' thread into the shed and thefeeding roll 11 continues to' feed the thread, the thread is temporarilycollected by means of the suction nozzle 14. The overall operationbetween a collecting nozzle and an insertion nozzle is disclosedin-U.S.- PatentNo. 3,024,814

issued March 13, 1962 to L. te Strake.

Then the shaft 17 returns to itsposition shown in FIG. 3. During themovement of the shaft17 from its position shown in FIG. 2 to itsposition shown in FIG. 3, the

Finally, thenozzle 19 comes into operation, thefloop being blown out ofthe shaft into the 'shed so' that the threads, the curved end or bightbetween the legs of the,

hairpin forming the selvedge proper.

Hence, blowing nozzles 18 and 19 work alternately. Between each periodof blowing of one of the nozzles there is a suction action in order toget a loop of the thread into the shed as follows:

Nozzle 1t; blows one leg of hairpin into the shed.

Shaft 17 sucks loop for other leg of hairpin.

Nozzle 19 blows said other leg of hairpin into the shed.

Shaft 17 sucks loop for first leg of the next hairpin.

Nozzle 18 blows said first leg of said next hairpin into the shed.

Shaft 17 sucks loop for other leg of said next hairpin and so on.

The shaft 17 and its operation are shown in detail in FIGS. 5-9. Nearthe open end 16 of the shaft 17 air jet holes or nozzles 23, 24 and 25,26 are provided which are situated in and communicate with the widenedends or mixing portions 27 and 28 of channels 29 and Ellcommunicatingwith the edges of a slit 31 formed in the shaft 17. Nozzle 18 is formedby mixing portion 28 and air jets 2,5 and 25; nozzle 19 is formed bymixing portion 27 and air jets 23 and 24. Channels 29 and 3% arecontinually in communication with each other. by the narrow nected tothe atmosphere via an opening 36 by a vent slit 6. The shaft 1'7 servesfor drawing the loop in the weft thread 12 to be blown into the shed,the approximately .the nozzles 23, 24 or 25, 2-5. A more detaileddescription of the principle of operation of Weft thread storage in ashaft is set forth in my copending application Serial No. 84,031 filedJanuary 23, 1961 and now US. Patent No. 3,110,325 issued November 12,1963, and the above US. Patent No. 3,024,814.

The enlargement 27 of the channel 29 forms a mixing tube for the primaryair from the jet nozzles 23 and 24 and the secondary air suppliedthrough the channel 29.

Similarly nozzles 25 and 26 are arranged near the channel 39. Theenlargement '28 of the channel forms a mixing tube for the primary airfrom the nozzles 25 and 26 and the secondary air supplied through thechannel 30.

Between the mixing tubes 27 and 28 the continuation of the slit 31allows passage of the loop of thread in and out. Because of the actionof the nozzles 23, 24 and 25, 26 a powerful air current in the channe.s29 and 3t? comes into existence. The thread situated in the channels 29and 30 is suspended in this air current and does not come into contactwith the walls of the channels 29 and 30, so that these walls cannotexert a braking action on the thread. The secondary air current throughthe channels 29 and 39 toward the mixing tubes 27'and 28 contributes ingiving to the thread initial velocity, so that the air nozzles needapply air friction contact on only a small part of the thread to beblown into the shed, in order to provide the required initial velocityto this thread. The nozzles 2'5 and 2 s or the nozzles 25 and 26 may beswitched on as desired, air being supplied to the nozzles 23 and 24through a hose 32 and to the nozzles 25 and 26 through a hose 33 andshut on and off by means of valves not shown. When the thread is drawninto the shaft 17 by means" of a suction device connectedto a suctionopening 34 (FIG,

9), which can be closed by a valve (not shown) in ahose 35 communicatingwith the opening 34-, the nozzles 23 and 2.4 or 25 and 26, respectively,are not in operation. (See copending application Serial No. 84,031, nowUS. Patent No. 3,110,325Qreferenced hereinbefore.)

'When either the nozzles 23 and 24 or the nozzles 25 and 2d are put intooperation the valve in the hose 35 is closed, so that air flow throughthe opening 3 1 is stopped.

At the same moment the interior of the shaft 17 is convalve (not shown)in a hose 37 coming into operation, in order to prevent the formation oftroublesome pressure Waves. (See copending application Serial No.84,031, now US. Patent No. 3,110,325, referenced above.) Through thisopening 36 secondary air can enter the channels 29 and 3t To facilitatethis entry of secondary air for the mixing 7 7 to the closed end toprovide the longest air thread suspension currents in channels 29 and30.

As appears from FIG. 9, the shaft may be made bent,

the air nozzles and the mixing tubes being positioned in the upper part40. The lower part may be provided with a transparent Wall 41 in orderto monitor the course of the thread in the shaft and to monitor whetheror notthe slits and channels are about to be clogged or to observe anyother operation desired. p

A driving mechanism for the shaft 17 is shown in FIG.

9. The shaft 17 is provided with a pin 42 in a bearing 43 of a support44 which is any suitable part of the loom.

A lever 45 is connected to the pin 42 and a rod :6 isconnected betweenthe lever 45 and a bell crank 47 pivotally mounted on a shaft 4-8. Aroller 49 is carried by an arm of the bell crank and abuts on a cam (notshown) or other control-device which acts periodically as a functionofthe stroke of the loom.

There has thus been described a weft inserting appar'atus for a weavingloom which comprises a shaft having formed therein a longitudinallyextending thread-receivingslit opening to the atmosphere at one end ofsaid shaft. The shaft also has formed therein a suction aper! tureadapted to be utilized to lower the pressure within the slit'whereby athread disposed adjacent the slit' openthread in a U-shaped loop when itis drawn into the slit.

the slit opening.

The shaft is provided with air nozzle means, shown in the specificationas an air nozzle formed within the shaft which communicates at one endwith one of said chan-' nels, the other end adapted to be utilized todirect a jet of air through the nozzle and into the channel to transporta thread disposed in the channel out into a shed.- it is to beunderstood that any air nozzle means which may be adapted to the useshown in here may be used to complete applicants invention.

The shaft may also have a vent aperture therein providing communicationbetween the atmosphere and the slit intermediatethe suction aperture andbe formed in the shaft communicating with the vent aperture, the slit,and/ or one of thechannels receiving the jet'of air, in order tofacilitate the flow of secondary'air; V Venting means may be provided toadmit air directly to the one of the channels as so deinto the channels.

sired.

In a preferred embodiment of the invention the shaft has formed thereinan enlargement of at least one'of the arate-part (as may also .be donewith the air nozzle, for

example), the separate part being disposed to form a con-i formed 7 Oneor more auxiliary channels may tinuation of and to communicate with saidone channel having the air nozzle therein or communicating therewith.The tube also communicates withthe slit so that the thread may be drawnin and jetted forth into the shed.

1. Apparatus to be utilized in a loom, comprising:

thread feeding means; a thread collecting means; thread clamping means;a shaft having formed therein a longitudinally extending threadreceiving slit, said shaft also having formed therein a suction apertureadapted to be utilized to lower the pressure within said slit whereby aIn conclusion, it is pointed out that while the illusv ture wherebysuction pull established through said suction aperture is strongerinsaid channels thereby maintaining said thread in a U-shaped loop; saidshaft having an, air nozzle formed therein communicating at one end withone of said channels, the other end adapted to be utilized to direct ajet of air through said nozzle and into said channel to transport athread disposed in said channel out into a shed; said shaft having avent aperture formed therein providing communication .between theatmosphe're and said slit intermediate said suctionaperture and saidslit opening. a V

4. Weft inserting apparatusfor a loom comprising a shaft having formedtherein a longitudinally extending thread-receiving slit opening to theatmosphere at one end of said shaft; said shaft also having formedtherein a suction aperture adapted to be utilized to lower the pressurewithin said slit whereby a thread disposedadjacent the slit opening isdrawn in a loop into said slit; saidshaft having channels larger thansaid slit formed lengthwise adjacent to and communicating withsaid slit;said chan- 'nels also communicating with said suction aperture wherebysuction pull established through said suction aperture is stronger insaid channels thereby maintaining said thread disposed adjacent saidslit is drawn in a first loop into said slit; said slit havingenlargedfirst and second channels formed lengthwise adjacent to andcommunicating with said slit, said channels also communicating with saidsuction aperture whereby suction pull. established through said suctionaperture is stronger in said channels thereby maintaining said thread ina U-shaped loop; first and second nozzles disposed adjacent the openingsof said first and second channels, respectively, of said shaft; saidfirst nozzle being adapted to blow an end of said first loop of threaddisposed in said slit into a shed thereby pulling the length of saidfirst loop in said slit into said shed; the other end of said threadbeing restrained by said thread clamping means; means operative aftersaid first nozzle has ceased operation to release said thread clampwhereby the suction pull in said slit is operative to draw a second loopof thread into said slit from said thread collecting means; meansoperative in response to said second loop of thread being pulled intosaid slit for severing and clamping said thread between said shaft andsaid thread feeding means; said second nozzle being adapted to blow saidsevered end of said thread into a shed thereby pulling the length ofsaid second loop into said shed.

2. Weft inserting apparatus for a loom comprising a shaft having formedtherein a longitudinally extending thread-receiving slit opening to theatmosphere at one end of said shaft; said shaft also having formedtherein a suction aperture adapted to be utilized to lower the pressurewithin said slit whereby a thread disposed adjacent the slit opening isdrawn in a loop into said slit; said shaft having channels larger thansaid slit formed lengthwise adjacent to and communicating with saidslit; said channels also communicating with said suction aperturewhereby suction pull established through said suction aperture isstronger in said channels thereby maintaining said thread in a U-shapedloop; said shaft having an air nozzle formed therein communicating atone end with one of said channels, the other end adapted to be utilizedto direct a jet of air through said nozzle and into said channel totransport a thread disposed in said channel out into a shed.

3. Weft inserting apparatus for a loom comprising a shaft having formedtherein a longitudinally extending thread-receiving slit opening to theatmosphere at one end of said shaft; said shaft also having formedtherein a suction aperture adapted to be. utilized to lower the pressurewithin said slit whereby a thread disposed adjacent the slit opening isdrawn in a loop into said slit;

said shaft having channels larger than said slit. formed lengthwiseadjacent to and communicating with said slit; said channels alsocommunicating with said suction aperthread in a U-shaped loop; saidshaft having an air nozzle formed therein communicating at one end withone of said channels, the other end adapted to be utilized to direct ajet ofvair through said nozzle and into said channel to transport athread disposedin said channel out into "a shed; said shaft having avent aperture formed therein I providing communication between theatmosphere and said slit intermediate said suction aperture and saidslit opening; said shaft also having formed therein anauxiliary channelcommunicating with said vent aperture, said slit and said one of saidchannels receiving said; jet of air to facilitate flow of secondary airinto said one of said 5. Weft inserting apparatus for a loom comprisinga shaft having formed therein a longitudinally extendingthread-receiving, slit opening to the atmosphere at one end of saidshaft; said shaft also having formed therein a suction aperture adaptedto be utilized to lower the 1 pressure within said slit whereby a threaddisposed adjacent the slit opening is drawn in a loop into said slit;said shaft having channels larger than said slit formedlengthwiseadjacent to and communicating with said slit; said channels alsocommunicating withsaidsuction aperture whereby suction pull establishedthrough said suction aperture is stronger in said channels therebymaintain? ing said thread in a U-shaped loop; said shaft having an airnozzle formed therein communicating at one end with 1 one of saidchannels, the other end adapted to be utilized to direct a'jet ofairthrough said nozzle and into said channel to transport a threaddisposed in said channel out into a shed; said shaft having'a ventaperture formed therein providing communication between the atmosphereand said one of said. channels to facilitate flow of secondary air intosaid one channel during operation of said air nozzle.

6. Weft inserting apparatus for a loom comprising a shaft having formedtherein a longitudinally extending thread-receiving slit opening to theatmosphere at one end of said shaft; said shaft also having formedtherein a suction aperture adapted to be utilized to lower thepressurewithin said slit whereby athread disposed adjacent said slit is drawn ina loop into said slit; said shaft having channels-larger than said slitformed lengthwise adjacent to and communicating with said slit; saidchannels also communicating with said suction aperture whereby suctionpull established through said suction aperture isstronger in saidchannels thereby maintaining said thread in a U-shapedjloop; at leastoneof said channels being enlarged for a portion of its length back fromsaid open shaft endjto form a mixing tube; said shaft having an airnozzle communicating at one end with said enlarged channel portion, theother end adapted to be utilized to direct a jet of air through saidnozzle and into said enlarged channel portion; said shaft having a ventaperture formed therein providing communication between the atmosphereand said slit intermediate said suction aperture and said mixing tube.

7. Weft inserting apparatus for a loom comprising a shaft having formedtherein a longitudinally extending thread-receiving slit opening to theatmosphere at one end of said shaft; said shaft also having formedtherein a sucin a U-shaped loop; at least one of said channels beingenlarged for a portion of its length back from said open shaft end toform a mixing tube; said shaft having an air nozzle communicating at oneend with said enlarged channel portion,- the other end adapted to beutilized to direct a jet of air through said nozzle and into saidenlarged channel portion; said shaft having a vent aperture formedtherein providing communication between the atmosphere and said slitintermediate said suction aperture and said mixing tube; said shaft alsohavingformed at least one auxiliary channel communicating with said ventaperture, said slit, and said one of said first-mentioned channelshaving said mixing tube formed at the end thereof to facilitate flow ofsecondary air into said one of said channels. I

8. Weft inserting apparatus for a loom comprising a shaft having formedtherein a longitudinally extending thread-receiving slit opening to theatmosphere at one end 'of said shaft; said shaft also having formedtherein a suction aperture adapted to be utilized to lower the pressure'within said slit whereby a thread disposed adjacent the slit opening isdrawn in a loop into said slit; said shaft having channels larger thansaid slit formed lengthwise adjacent to and communicating with saidslit; said channels also communicating with said suction aperturewhereby suction pull established through said suction aperture isstronger in said channels thereby maintaining said thread in a U-shapedloop; and air nozzle means com-: municating with one of said channelsadapted to direct 'a jet of air through said channel to transport athrea t out of said channel into a shed. a

9. Weft inserting apparatus for a loom comprising a shaft having formedtherein a longitudinally extending thread-receiving slit openingto theatmosphere at one end of said shaft; said shaft also having formedthereina suction aperture adapted to be utilized to lower the pressurewithin said slit whereby a thread disposed adjacent the .slit opening isdrawn in a loop into said slit; said shaft having channels larger thansaid slit formed lengthwise adjacent to and communicating with saidslit; said chanif nels also communicating with said'suction aperturewhereby suction pull established through said suction aperture -isstronger in said channels thereby maintaining said thread in a U-shapedloop; air nozzle meanscommunicating with one of said channels adaptedtodirect a jet of air through said channel to transport a thread out ofsaid channel into a shed; and venting means for admitting -air from theatmosphere to said one of said channels having said air nozzle meanscommunicating therewith.

l0. Weft inserting apparatus for a loom comprising a shaft having formedtherein a longitudinally extending thread-receiving slit opening totheatmosphere at one end of said shaft; said shaft also having formedtherein a suction aperture adapted to beutilized to lower :the

pressure within said slit whereby a thread disposed adjacent the slitopening is drawn in a loop into said slit;

"said shaft having channels larger than said slit formed lengthwiseadjacent to and communicating with said slit;

said channels also communicating with said suction aper-' J r "turewhereby suction pull established through said suction aperture isstronger in said channels thereby maintaining said thread in a U-shapedloop; a mixingtube larger'in cross-section than one of said channelsdisposed to form a continuation of and tocommunicate with said onechannel; said tube also communicating with said slit; andair nozzlemeans communicating with said mixing tube adapted to direct a jet of airthrough said mixing tube to transport a thread disposed in said onechannel and said tube out into a shed. i

References Cited in'the file of this patent UNITED STATES PATENTS2,925,833 Te Strake Feb} 23, 1960 Te Strake Mar. 13, 1962

1. APPARATUS TO BE UTILIZED IN A LOOM, COMPRISING: THREAD FEEDING MEANS;A THREAD COLLECTING MEANS; THREAD CLAMPING MEANS; A SHAFT HAVING FORMEDTHEREIN A LONGITUDINALLY EXTENDING THREAD RECEIVING SLIT, SAID SHAFTALSO HAVING FORMED THEREIN A SUCTION APERTURE ADAPTED TO BE UTILIZED TOLOWER THE PRESSURE WITHIN SAID SLIT WHEREBY A THREAD DISPOSED ADJACENTSAID SLIT IS DRAWN IN A FIRST LOOP INTO SAID SLIT; SAID SLIT HAVINGENLARGED FIRST AND SECOND CHANNELS FORMED LENGTHWISE ADJACENT TO ANDCOMMUNICATING WITH SAID SLIT, SAID CHANNELS ALSO COMMUNICATING WITH SAIDSUCTION APERTURE WHEREBY SUCTION PULL ESTABLISHED THROUGH SAID SUCTIONAPERTURE IS STRONGER IN SAID CHANNELS THEREBY MAINTAINING SAID THREAD INA U-SHAPED LOOP; FIRST AND SECOND NOZZLES DISPOSED ADJACENT THE OPENINGSOF SAID FIRST AND SECOND CHANNELS, RESPECTIVELY, OF SAID SHAFT; SAIDFIRST NOZZLE BEING ADAPTED TO BLOW AN END OF SAID FIRST LOOP OF THREADDISPOSED IN SAID SLIT INTO A SHED THEREBY PULLING THE LENGTH OF SAIDFIRST LOOP IN SAID SLIT INTO SAID SHED; THE OTHER END OF SAID THREADBEING RESTRAINED BY SAID THREAD CLAMPING MEANS; MEANS OPERATIVE AFTERSAID FIRST NOZZLE HAS CEASED OPERATION TO RELEASE SAID THREAD CLAMPWHEREBY THE SUCTION PULL IN SAID SLIT IS OPERATIVE TO DRAW A SECOND LOOPOF THREAD INTO SAID SLIT FROM SAID THREAD COLLECTING MEANS; MEANSOPERATIVE IN RESPONSE TO SAID SECOND LOOP OF THREAD BEING PULLED INTOSAID SLIT FOR SEVERING AND CLAMPING SAID THREAD BETWEEN SAID SHAFT ANDSAID THREAD FEEDING MEANS; SAID SECOND NOZZLE BEING ADAPTED TO BLOW SAIDSEVERED END OF SAID THREAD INTO A SHED THEREBY PULLING THE LENGTH OFSAID SECOND LOOP INTO SAID SHED.